Auto Service World
Feature   April 1, 2011   by Tom Venetis, Editor

What Is Happening With Dexos

Dexos specifications brings challenges to the oil change for independents

Last year, SSGM took a close look at the new motor oil specifications coming for 2011. Particular attention was focused on the new GF-5 standard developed by the International Lubricant Standardization and Approval Committee (ILSAC). GF-5 is a step-up from the previous GF-4 standard released for 2005 vehicles. It is made to meet criteria for improved resistance to oxidation caused by higher engine temperatures, increased detergency for the prevention of engine deposits, added protection against engine friction and improvements overall in fuel economy of vehicles while at the same time helping reduce emissions.
As the new GF-5 specification was being released, General Motors was putting the final touches on its own dexos motor oil specification to be used for factory fills and service fills on 2011 model-year General Motors vehicles worldwide. There are two dexos standards, dexos1 and dexos2.
“The dexos specification was developed in 2007 and the first GM vehicles started using dexos approved oils in 2009,” said Eric Johnson, GM lubricants engineer, General Motors. “The dexos specification utilizes ACEA/CEC engine tests, ASTM/API engine tests, and in-house engine tests that results in a more robust specification that gives our current customers the latest in engine oil technology and provides a solid platform for GM engineers to bring the latest engine technology to market sooner which ultimately benefits our customers and the environment.”
According to the GM dexos Information Center (, dexos is blended to provide “significant wear protection, improved piston cleanliness, a reduction in volatility and oil consumption, enhanced aeration control for improved fuel efficiency, and better oxidation properties.” The online information center further adds “dexos is recommended by GM for use in all its vehicles except those with Duramax diesel engines requiring the use of API CJ-4 engine oil. Dexos is fully backward-compatible and can be used in older vehicles. It is specified in the owner’s manual for all 2011 and later model years, with the exception of Europe where dexos is specified starting in model year 2010. Dexos1 is designed for use with gasoline engines and replaces GM-LL-A-025, GM6094M and GM4718M. Dexos2 is designed for use with light-duty diesel engines and replaces GM-LL-B-025 and GM-LL-A-025.”
Blenders who have come on-board with dexos, can be found here:
It would all seem pretty straight forward, except there is some confusion right now amongst some independents and shops specializing in rapid oil changes over how dexos differs from the recently agreed ILSAC GF-5 specification, and what it means for vehicle oil changes.
ILSAC GF-5 and dexos would seem to some in the aftermarket to be very similar. So the question is why not use an ILSAC GF-5 spec motor oil in a new GM vehicle? GM’s Johnson said that similarity is only on the surface: “GM would expect a formulation approved to dexos1 to meet the GF-5 requirements. A GF-5 oil may not meet the dexos specifications.”
According to the dexos information center, drivers of General Motor’s newest vehicles who use “oils other than authentic dexos products could result in reduced engine performance or damage not covered under warranty.”
Johnson added: “GM, as do other manufacturers, require a product that meets their specification to be used in that application. This is no different than it has been in the past. Manufacturers require their specification because that is what has been tested in that application. Specifically, using engine oil licensed to the dexos specification means that their engine will be operating at a very high level throughout the service life of the oil. Our warranty statement has been consistent for many years.”
Not everyone, however, is fully behind dexos. As one can see from the list published on the dexos Information Center, there are some oil blenders who are absent. SSGM Magazine contacted several oil makers to talk about the dexos standard – those who do have licensed dexos motor oils and those who do not currently have a dexos-licensed product. Many turned down the opportunity to talk on the record, some citing ongoing licensing negotiations with General Motors and others saying they did not want to talk about the issues surrounding dexos which have come up in other media outlets.
Anthony Stadelman, director of marketing with Wakefield Canada Inc. said GM’s position is not at all unusual. “GM has said it wants (a) more stringent specification for their vehicles and they have ‘bumped’ a couple of the minimum requirements on a couple of key characteristics.” He added “BP Castrol are currently undecided and continue to talk to GM about the license.”
One company that has come out strongly against the dexos licensing requirements is Ashland Inc., makers of Valvoline lubricants even though the company has said it has oils that meet the dexos requirements.
“We have products that meet all the requirements and have gone through all the testing, but we chose not to license them,” said Thom Smith, vice-president for branded lubricant technology, Valvoline. “Additive suppliers routinely submit formulation for approval of specifications and we chose formulation for our products that were approved for licensing. We have three products that meet all the requirements: SynPower 5W-20 and 5W-30, and DuraBlend 5W-30.
Smith added GM created the dexos specification by “taking some of the requirements of API, some of the requirements for ACEA and some engine tests on their own, and put together a specification of their own. It does take some additional chemistry to pass all those tests as compared to the basic ILSAC GF-5 type products. There are also some different physical requirements that are more stringent than API.”
For some oil makers the issue is not just around the standard, but around the licensing program GM has created for dexos and over some of the language GM has used for issues of warranty claims. On March 7, 2011 Oil Express’ Carole Donoghue reported lube oil marketers were approaching the United States’ Federal Trade Commission to voice their complaints of that program. According to the report, in the letter sent to the FTC, lube oils firms and gas dealers point to the US Mangnusson-Moss Warranty Act and the Federal Trade Commission Act that make it illegal for a dealer or manufacturer to void a warranty because a consumer did not have a vehicle serviced at a dealership. As well, there are questions about the licensing and royalty fees around dexos. According to Oil Express, the fee works out to about 36 cts/gal and is based on market share; GM said the monies raised by the fees will be used to fund development of engine tests for the oil and to operate quality monitoring programs.
“We have chosen not to license because it adds to the cost of the oil without providing any additional benefit to the consumer,” said Smith. “The GF-4 oils performed perfectly well in 2010 vehicles, so there is no reason to believe that GF-5 products would not also perform well in new vehicles.
“There is another interesting angle as well for certain fleet customers of GM,” he continued. “GM has indicated that those customers are fine to use the API-specification oil without voiding the warranty. The reason is that GM is allowing (the fleet customers) to do that is that between model year 2010 and 2011, the engine design is no different. There is no technological reason why you would have to use dexos oil. This raises the question: why is GM trying to force individual consumers to use the more expensive dexos-compliant oil?”

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